Rotary low pressure gas pump and method of operating the same



Sept. 8, 1959 o. FUERST ETAL ROTARY LOW PRESSURE GAS PUMP AND METHOD OF OPERATING THE SAME Filed Oct. 5, 1955 6 Sheets-Sheet 1 I INVENTOR Lon J GT9)? 6':

and Usu/z/d Fuersl ATTORNEY p 1959 0. FuERsT ET AL 2,902,943

ROTARY LOW PRESSURE GAS PUMP AND METHOD OF OPERATING THE SAME Filed. Oct. 5, 1955 6 Sheets-Sheet 2 INVENTOR Leon J, Greff Sr: and 0514 310 FUR/"Sf ATTORNEY P 8, 1959 o. FUERST ET AL ,90

ROTARY LOW PRESSURE GAS PUMP AND METHOD OF OPERATING THE SAME Filed Oct. 5, 1955 5 Sheets-Sheet 3 JNVENTOR Leon J. Greffr and Usufiald Fuersl ATTORNEY Sept. 8, 1959 o. FUERST ETAL 2,902,943

ROTARY LOW PRESSURE GAS PUMP AND METHOD OF OPERATING THE SAME Filed 001;. 5, 1955 a Sheets-Sheet 4 INVENTOR Leon J Gre/f Sr and 0314 2220 Fuersf ATTORNEY o. FUERST ETAL Sept. 8, 1959 ROTARY LOW PRESSURE GAS PUMP AND METHOD OF OPERATING THE SAME Filed Oct. 5, 1955 6 Sheets-Sheet 5 'Sept. 8, 1959 o. FUERST ETAL 2,902,943

ROTARY LOW PRESSURE GAS PUMP AND mamon or OPERATING THE sm:

6 Sheets-S 6 Filed Oct. 5, 55

Leon J Gr Sr and Fu rst a I I T O EY United Sttes Patent ROTARY LOW PRESSURE GAS PUMP AND METHOD OF OPERATING THE SAME Oswald Fuerst and Leon James Greif, Sr., New Orleans, La., assignors to Superior Industries, Inc., New Orleans, La., a corporation of Louisiana Application October 5, 1955, Serial No. 538,640

Claims. (Cl. 103--136) This invention relates to a rotary low pressure gas pump and method of operating the same. The invention further relates to a pump of the above class particularly designed for volatile fluids such as propane, butane, anhydrous ammonia, etc.

Still further the invention relates to a carbon seal for preventing the escape of the above-mentioned volatile fluids around the driving shaft of the pump during its operation.

One important object of the invention is to provide a novel pump embodying a stator, a rotor carrying vanes or blades projecting from the rotor and wherein the engagement of the blades with the stator is accomplished by the utilization of a portion of the fluid taken from the delivery outlet of the pump.

A second important object of the invention is to provide a novel pump of this class wherein the stator is internally provided with a cam surface against which the vanes or blades impinge.

A third important object of the invention is to provide means whereby the inner ends of such blades are maintained without the use of springs or the like under pressure of fluid derived from the outlet side of the pump whereby the outer edges of these blades are kept in positive contact with the cam surface on the interior of the stator.

A fourth important object of the invention is to provide a construction in such a pump whereby outward pressure tending to project the vanes or blades is maintained constantly at the equivalent of the pressure in the outlet from the pump.

A fifth important object of the invention is to provide a novel form of packing surrounding the driving shaft of a pump, the packing being designed to prevent the escape of fluid around the shaft from the pump.

A sixth important object of the invention is to provide a packing of this class which will resist the deleterious effects of carbonization in such a packing.

With the above and other objects in view, the invention consists in general of certain novel details of construction and combinations of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly claimed.

In the accompanying drawings, like characters of reference indicate like parts in the several views, and:

Fig. 1 is a vertical median section to a pump constructed in accordance with this invention and showing a section through the packing arrangement. a

Fig. 2 is a view from the right hand side of Fig. 1 showing the elevation of the pump as viewed from that side.

Fig. 3 is a section on the line 33 of Fig. 1.

Fig. 4 is a section on the line 44 of Fig. 1.

Fig. 5 is a section on the line 55 of Fig. 1.

Fig. 6 is an enlarged detailed view of a portion of Fig. 1.

Fig. 7 is an enlarged detailed section on the line 77 of Fig. 5.

Fig. 8 is an enlarged detailed view on the line 88 of Fig. 5.

Fig. 9 is an enlarged section on the line 99 of Fig. 1.

Fig. 10 is an enlarged detailed section on the lin 10-10 of Fig. 1.

Fig. 11 is an enlarged detailed section on the line 11-11 of Fig. 1.

In the construction of this pump, as shown in the present drawings, there is provided a body 10 of substantially cylindrical exterior form. This body 10 has a portion provided with an interior surface 11 of cam shaped form. This cam shaped surface has two oppositely disposed inwardly projecting high points 12. Mounted within and axially of the body is a shaft 13. The body just described constitutes the body of the stator of the pump. On the shaft 13 is fixed a cylindrical rotor 14, the diameter of which is equal to the space between the high points 12. This rotor, through its contact with the high points 12 provides a pair of lunate chambers 15. In this rotor is formed a circumferally spaced series of radial slots 16, in each of which is mounted a blade or vane 17, which is projectable radially from the respective slot in which it is held and which, when so projected, contacts with the cam surface inside of the stator.

Now it is common in pumps of this description to have springs or other mechanical means for maintaining these blades in the cam contact. In the present instance this is not done by any levers, springs or the like, but is done by the utilization of fluid under pressure derived from the action of the pump.

At one end of this body there are carried certain chambers, the description and operation of which will hereinafter be described. The other end of the body is, as shown in Fig. 1, open, but this end is closed by a circular closure 18 and this closure is secured to the open end of the body by bolts 19 and is supported on a standard 20, which carries the pump and which is adapted to be seated on any suitable foundation. This closure is likewise of cylindrical form exteriorly and at its face on the body 18 is provided an annular channel 21. This channel 21 is so dimensioned that it communicates with the inner ends of the slots 16. Now the shaft 13 is the means for rotating the rotor within the stator. This closure 18, as is shown in Figs. 1 and 6, is provided with an inlet passage 22. At the face of closure which confronts the body 10 there is formed an annular channel 21 which is in constant communication with the inlet 22.

It will be seen from the portion of the description heretofore given that the drive connection, base and rotor of the pump are all capable of handling as a single assembly. The body 10 is secured on one of its ends to this assembly by the bolts 19.

At its opposite or front end, it receives the housing 27 in which the inlet and outlet connections and passages are formed. The outer face of the housing 27 is closed by a bolted-on plate 29, this method of assembly making the pump very easy to disassemble.

Within the housing 27 an inlet 52 communicates with the inner, inlet chamber 23, having a pair of ports 24, each one connecting the chamber 23 with one of the two lunate chambers 15. The housing casting also provides another pair of port channels 26 leading to the outer, exhaust chamber 25 having a delivery connection 28. Thus, all of the internal connections of the pump are contained in a single casting to which both the external inlet and outlet connections are made.

Now as to be understood this far, upon rotation of the rotor, fluid will enter between the rotor to the lunate tion ,as radial and. thrust bearings.

and effect a tight charnbering of the fluids drawn in and expelled.

The closure 18 is provided-with an. outwardly extending. hollow boss 30 where is located the outer race 31 ofa ball bearing; the inner race 32 of whichfits on the shafts13. Also in this boss there is located a second ballbearing-33, the two ball bearings: actingin combina- Also the: boss 30 extends, outward and. in the outer endof this extension there isscrewed a collar 41 which at the inner end bears against the outer race of ball bearing 33.. Within the extension 3.0 and screwed against inner race of bearing 33,. there is adjusting nut-34'. Inner races of. bearings 33 and 32 which engage shaft 13, and which at their inner .ends abuts against spacer collar .42 holding inner races ofbothbearingsin place. Inner races of both bearings 33 and 3.2 and spacer collar 42 arelocked together by bearings lock nut 34 which is screwed on shaft 13.

.Inthe adjustment nut'48 there is provided a series of holes 49 for adjusting nut .48. These holes 49 also provide agrease opening to 44 normally closed by grease cap-45; holes 49 also communicate with annular space 50 and. the diflerent ball bearings and thereby upon being filled with grease, keeps these ball bearings lubricated. In the extreme outer end of the extension 30 is screwed a collar 41 arrangedto form a dust trap. 47. This: collar bears against the outer bearings and by reason of the dust trapkeeps. the bearings clean of dust and dirt.

It is obvious that, while this particular form of bearing and dust trapmay be as here shown, other forms may be used in connection with the main body of the invention.

Operation As stated, the pump of this invention is intended to operate with: such. fluids as will flood the chambers and passages thereof. Upon opening of the valves (not shown) in. the linesv connecting the pumpin the system,

liquid will flow through the inlet 52. into the chamber -23, through ports 24 into the. two chambers 15. Since at Liquid is drawn. through. the ports 24 into the expanding pockets formed by the surfacell', the rotor 14 and outwardly moving vanes 17. As the vanes advance from the horn of the lunate chamber 15 to the body thereof, the communication with port 24 is cut off and the opposite horn of lunate chamber is approached opening the trapped spaces to port 26 whence the liquid flows out through chamber 25 to outlet 28. The build-up of pressure in the outlet side of the pump insures a continued outward pressure upon the vanes 17 to seal their outer faces against the surface '11-.

What is claimed as new is:

1. In a pump, a hollow body, a rotor mounted for rotation within said body and forming with the inner surface of said body, at least one lunate chamber, a plurality of radial slots in said rotor, vanes radially movable in said slots, extending to contact said inner body surface at their outer ends; an annular channel in contact with said rotor and in fluid communication with the inner ends of each of the slots in said rotor; a first wall closing one axial side of said pump body, a second wall closing the other axial side of said pump body, first additional walls, forming with said second wall an inlet chamber concentric with the pump body and outwardly spaced thereof, a port leading through the second wall from the inlet chamber to the lunate chamber in the area where the vanes are moving outwardly of said rotor and elongated in the direction of rotation; further additional walls forming with one of said first additional walls, an outlet chamber coaxial with said inlet chamber and said pump body and located beyond said inlet chamber with respect to said pump body, a channel leading from the lunate chamber to the outlet chamber through said second wall and through said one first additional wall in the area where the vanes are being forced radially inward of said rotor, said second wall, said first additional walls and said further additional walls being separately formed from said pump body and said first wall and being removable from said pump body for dismantling said pump; and a conduit leading from the outlet chamber to said annular channel for leading pressure fluid to the inner ends of the rotor slots to force the vanes outwardly against the inner body surface.

2. The structure of claim 1 wherein the walls of the inlet chamber form, with the second wall of the pump chamber, a single casting to close the pump body and wherein a wall of the outlet chamber forms, with the inlet chamber casting, the outlet chamber.

3. The structure of claim 1 wherein the walls of the inlet and outlet chambers are cast as a single unit, separable from the pump body.

4. The structure of claim 3 wherein said annular channel is formed in said first wall closing the end of the pump body opposite the casting containing the inlet and outlet.

5. The structure of claim 1 wherein said annular channel is, formed in said first Wall closing the end of the pump body opposite the inlet chamber.

References Cited in the file of this patent UNITED STATES PATENTS 1,087,181 Pitman Feb. 17, 1914 1,093,005 Myers Apr. 14, 1914 1,580,713 Ensign Apr. 13, 1926 1,670,229 Balsiger May 15, 1928 1,989,900 Vickers Feb. 5, 1935 2,099,193 Brightwell Nov. 16, 1937 2,255,785 Kendrick Sept. 16, 1941 2,391,577 Larson Dec. 25, 1945 2,523,317 McGill Sept. 26, 1950 2,631,540 Baugh et al Mar. 17, 1953 2,632,398 Ferris Mar. 24, 1953 2,633,292 Voznica Mar. 31, 1953 2,653,550 Gardiner et al. Sept. 29, 1953 2,653,551 Rosaen Sept. 29, 1953 2,720,171 Harrington et al. Oct. 11, 1955 2,728,615 McCombie Dec. 27, 1955 2,763,216 Klessig Sept. 18, 1956 FOREIGN PATENTS 751,301 Great Britain June 27, 1956 

